Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
• On clean paper, show your work. Circle your answer. • 1. A rooster with gray feathers is mated with a hen of the same phenotype. Among their offspring, 15 chicks are gray, 6 are black, and 8 are white. What is the simplest explanation for the inheritance of these colors in chickens? 1 • A rooster with gray feathers is mated with a hen of the same phenotype. Among their offspring, 15 chicks are gray, 6 are black, and 8 are white. What offspring would you predict from the mating of a gray rooster and a black hen? 2 • In some plants, a true-breeding, redflowered strain gives all pink flowers when crossed with a white-flowered strain: RR (red) x rr (white) ---> Rr (pink). If flower position (axial or terminal) is inherited as it is in peas what will be the ratios of genotypes and phenotypes of the generation resulting from the following cross: axial-red (true-breeding) x terminal-white? What will be the ratios in the F2 generation? 3 trait dominant recessive flower position axial (A) terminal (a) Stem length tall (T) dwarf (t) Seed shape round (R) wrinkled (r) • If a plant that is heterozygous for all three characters were allowed to self-fertilize, what proportion of the offspring would be expected to be as follows: (Note - use the rules of probability (and show your work) instead of huge Punnett squares) a. b. c. d. homozygous for the three dominant traits homozygous for the three recessive traits heterozygous homozygous for axial and dwarf, heterozygous for seed shape 4 • In sesame plants, the one-pod condition (P ) is dominant to the three-pod condition (p ), and normal leaf (L ) is dominant to wrinkled leaf (l) . Pod type and leaf type are inherited independently. Determine the genotypes for the two parents for all possible matings producing the following offspring: 318 one-pod normal, 98 one-pod wrinkled 323 three-pod normal, 106 three-pod wrinkled 401 one-pod normal 150 one-pod normal, 147 one-pod wrinkled, 51 three-pod normal, 48 three-pod wrinkled e. 223 one-pod normal, 72 one-pod wrinkled, 76 three-pod normal, 27 three-pod wrinkled a. b. c. d. 5 • A man with group A blood marries a woman with group B blood. Their child has group O blood. What are the genotypes of these individuals? What other genotypes and in what frequencies, would you expect in offspring from this marriage? 6 • Phenylketonuria (PKU) is an inherited disease caused by a recessive allele. If a woman and her husband are both carriers, what is the probability of each of the following? a. all three of their children will be of normal phenotype b. one of the three children will have the disease c. all three children will have the disease 7 • The genotype of F1 individuals in a tetrahybrid cross is AaBbCcDd. Assuming independent assortment of these four genes, what are the probabilities that F2 offspring would have the following genotypes? a. b. c. d. e. aabbccdd AaBbCcDd AABBCCDD AaBBccDd AaBBCCdd 8 The pedigree below traces the inheritance of alkaptonuria, a biochemical disorder. Affected individuals, indicated here by the filled-in circles and squares, are unable to break down a substance called alkapton, which colors the urine and stains body tissues. Does alkaptonuria appear to be caused by a dominant or recessive allele? Fill in the genotypes of the individuals whose genotypes you know. What genotypes are possible for each of the other individuals? 9 • A man has six fingers on each hand and six toes on each foot. His wife and their daughter have the normal number of digits (5). Extra digits is a dominant trait. What fraction of this couple's children would be expected to have extra digits? 10 The pedigree below traces the inheritance of a vary rare biochemical disorder in humans. Affected individuals are indicated by filled-in circles and squares. Is the allele for this disorder dominant or recessive? What genotypes are possible for the individuals marked 1, 2, and 3. 11 • • In fruit flies, eye color is a sex linked trait. Red is dominant to white. What are the sexes and eye colors of flies with the following genotypes? X R X r _________ X R Y __________ X r X r __________ X R X R ____________ X r Y ____________ • What are the genotypes of these flies: white eyed, male ____________ red eyed female (heterozygous) ________ white eyed, female ___________ red eyed, male ___________ • Show the cross of a white eyed female X r X r with a redeyed male X R Y . 12 • Show a cross between a pure red eyed female and a white eyed male fruit fly (sex-linked). What are the genotypes of the parents: ___________ and _______________ What percent of offspring are: white eyed, male ____ white eyed, female ____ red eyed, male ____ red eyed, female ____ 13 • In humans, hemophilia is a sex linked trait. Females can be normal, carriers, or have the disease. Males will either have the disease or not (but they won’t ever be carriers) X H X H = female, normal X H X h = female, carrier X h X h = female, hemophiliac X H Y = male, normal X h Y= male, hemophiliac Show the cross of a man who has hemophilia with a woman who is a carrier. What is the probability that their children will have the disease? __________ male children?_____________ female children?_____________ 14 • A woman who has hemophilia marries a normal man. How many of their children will have hemophilia, and what is their sex? 15